Samsung SONOACE R5 Manual do Utilizador descarregar pdf (Página 42)

1-26

User Manual

dierent tissues and organs have dissimilar attenuation characteristics. In water, there is almost no

attenuation. In the body, and particularly in water tank measurements, non-linear propagation and

saturation losses occur as pulse voltages increase.

The display accuracy estimates take into account the variability ranges of probes and systems,

inherent acoustic output modeling errors, and measurement variability. Display accuracy estimates

are not based on errors in, or caused by measuring according to, the AIUM measurement standards.

They are also independent of the eects of non-linear loss on the measured values.

Control aecting the indices

As various system controls are adjusted, the TI and MI values may change. This will be most apparent as

the POWER control is adjusted; however, other system controls will aect the on-screen output values.

■

Power

Power controls the system acoustic output. Two real-time output values are on the screen: a TI and

a MI. They change as the system responds to POWER adjustments.

In combined modes, such as simultaneous Color, 2D-mode and pulsed Doppler, the individual

modes each add to the total TI. One mode will be the dominant contributor to this total. The

displayed MI will be from the mode with the largest peak pressure.

2D-mode Controls

■

2D-mode size

Narrowing the sector angle may increase the frame rate. This action will increase the TI. Pulse

voltage may be automatically adjusted down with software controls to keep the TI below the

system maximums. A decrease in pulse voltage will decrease MI.

■

Zoom

Increasing the zoom magnication may increase frame rate. This action will increase the TI. The

number of focal zones may also increase automatically to improve resolution. This action may

change MI since the peak intensity can occur at a dierent depth.

■

Persistence

A lower persistence will decrease the TI. Pulse voltage may be automatically increased. An increase

in pulse voltage will increase MI.

1 2 ... 37 38 39 40 41 42 43 44 45 46 47 ... 453 454

Sem comentários

Samsung SONOACE R5 Manual do Utilizador Página 42